The field of the invention is a process for providing an acceptable fragrance into automobiles and other vehicles, both ground and air. The process provides stable odor over time in a uniform formulation that does not deposit on the surface of glass or plastic, causing unacceptable fogging.
The use of fragrant materials in environmental areas has a long history. Many patents exist for devices for applying fragrance to the air of buildings and vehicles. They primarily deal with mechanisms of application rather than the chemical and physical properties of the aromas themselves. Specifically, no prior patent concerns the creation of aromas satisfying all the requirements of the automotive industry.
Fragrances are complicated mixtures of chemicals that if exposed to air for extended periods of time undergoes significant alteration in odor. There are two major reasons for this change. The first is the fact that the so-called top note of the fragrance is composed of compounds that volatilize rapidly, and become depleted from the fragrance composition. The second is the fact that many fragrance compounds undergo oxidation when exposed to air. This oxidation results in a state sometimes referred to as rancidity. These two pathways result in an unacceptable change in the fragrance over time.
The methods of dispensing odors often involve evaporation from a substrate such as a paper blotter or plastic film. Such methods result in the release of selective components over time, continually changing the odor character. Spraying the aroma by pump or aerosol delivers a fragrance of uniform quality over time, and this is the preferred method of this invention.
The area in which there is a long felt need for improved fragrance delivery is within the automobile. The automobile offers a number of challenges to applying fragrance over an extended time. The first is the fact that fragrance compositions exposed to the air will undergo loss of top note and be susceptible to rancidity. The second is the fact that fragrance compounds will condense on the glass in an automobile, giving a phenomenon known as fog.
The Society of Automotive Engineers has advanced a test method (SAE J1756) which is applied to all materials used in the automobile. This method, entitled xe2x80x9cTest procedure to determine the fogging characteristics of interior automotive materialsxe2x80x9d, is used on all products that are used inside automobiles. Standard fragrances contain many compounds that do not pass this test either alone or in combination with others.
SAE J1756 tests the tendency of interior materials used in automobiles and other vehicles to produce a light-scattering film (fog) on a glass surface or to produce a measurable deposit on aluminum foil. Fog is defined as the deposit of an undesirable light-scattering film on the interior glass surface of a vehicle. Fog Number, determined by a photometric method, is the quotient, expressed as the 60 degree reflectance value of a glass plate with fogging deposits and the 60 degree reflectance of the same glass plate without fogging deposits, multiplied by 100. The basic components of the fog test unit are a chamber that can be heated, and a glass plate that can be cooled.
The need for a fragrance delivery system and compositions for such delivery that is (a) chemically uniform with time, (b) is resistant to oxidation and rancidity, and (c) will pass the SAE J1756 test, has not been recognized by the fragrance industry. It was not until the process of the present invention that compositions passing the SAE J1756 test as well as methods for their delivery were attained.
Fragrances are not one component systems: rather they are typically complex mixtures of ingredients that interact with each other to produce an appealing odor. It is possible that a material that causes fogging when tested alone will not have an adverse effect when a small amount is in a blend. Since single materials do not allow the diversity of aromas characteristic of commercial fragrances, the examples show simple blends that allow the creation of a variety of odors. The examples are constructed totally of nonfogging materials. The solvents allow cost reduction, dilution of strong odorants, and prevention of freezing in frigid climates.
Objective of the Invention
It is the objective of the present invention to provide fragrance compositions and a method of delivering them that are chemically uniform, oxidatively stable, and are non-fogging on automotive glass.
Summary of the Invention
Fragrances consist of a diverse mixture of chemical types, including hydrocarbons, alcohols, esters, aldehydes and ketones, heterocyclics, Schiff bases, and phenols. Natural products consisting of complex mixtures are used, such as citrus and flower oils. In addition to aroma chemicals, solvents and surfactants are often included in fragrance compositions to reduce cost, dissolve solid materials, or modify the solubility characteristics: examples are dipropylene glycol, diethylene glycol, benzyl benzoate, polysorbate 20 and nonoxynol 9.
To satisfy this invention, aroma materials must be selected either individually or in combination which produce pleasant scents or which can help mask unpleasant odors such as smoke and decaying food. In addition, fragrances having desired properties as determined by studies in aromachology will have special value.
Studies have proven that fragrances can effect mood and alertness, based on the transmission of olfactory information to the limbic system of the brain. In particular, research has shown that aromas can increase driver awareness and thus enhance safety. This invention includes specific materials of functional as well as aesthetic value.
The fragrance compositions useful in the practice of the present invention are composed of (a) solvents, (b) aroma chemicals and (c) surfactants. In order to be useful in the practice of the present invention, each component must pass SAE-J1756 having a minimum fog number of 60. Within the broad guidelines of SAE-J1756, individual vehicle manufacturers have specified exact criteria.
Several series of fogging tests on aroma chemicals and solvents have been performed (Reliable Analysis, Troy, Mich.). To conform as closely as possible to automotive requirements, General Motors test procedure GM9305P was employed. Samples were subjected to 95xc2x0 C. for 6 hours in a Hart Fog Chamber (Model 0011, S/N 125) and a 38xc2x0 C. cooling plate. The samples were conditioned for 16 hours in the laboratory environment. Gloss measurements were made (BYK-Gardner Micro TRI Gloss Meter), and microscopic examination (40xc3x97 magnification) performed. A minimum fogging number of 60 was required. Test materials can fail for a high fog number, the presence of droplets, or crystal formation